Q. Confused About Computer Lenses
We're confused about which lenses work best for presbyopes who work at a computer, especially the lenses that look like a progressive addition lens but without a narrow progressive channel. What is this type of lens called?

A.
I once called this type of lens "single vision progressives" which seemed to be a good name but one that most people did not understand. These lenses have also been called "occupational progressives" but the most appropriate term for this category of lens seems to be "variable focus" single vision lens.

Essentially, they are progressives that provide a much wider field of view for near and intermediate with restricted vision in the distance. Like PALs, they have no visible lines and provide smoothly changing power as the eye traverses from near (16 inches) to intermediate (17 to 30 inches) to some 10 feet from the viewer. They are ideal for computer use and other office tasks that don't require sharp vision in the distance because they allow the wearer to see well enough in the distance to recognize people coming in the office door.

Q. Which Poly is Best?
I'm interested in your opinion on proprietary polycarbonate sun lenses. How effective do you think they are in blocking UV rays compared with other sunglass lenses made with other poly materials?

A.
The UV blocking ability of polycarbonate is an inherent property of the resin from which the lenses are made. As a result, any lenses made of poly will fully block the hazardous portion of ultra violet light. Most producers of over-the-counter sunglasses now label their sunglasses if they block UV. Any time you see sunglass lenses identified as made of polycarbonate, you can be sure they block UV.

Q. Is There a Law?
Do any states require by law that an optometrist's office use only polycarbonate lenses on children? I work for an insurance company and as a rule of thumb we don't cover polycarbonate lenses for our members. They have to pay additional monies for this service, but if it's state law that a child must wear them, we would need to change our basic coverage for children.

A.
We contacted the American Optometric Association to see if this was a subject that they had tracked. AOA Legal Counsel Tom Eichhorst had his staff conduct a search of state statutes for any reference to the word "polycarbonate." They could find no instance of a state statute that mandated the use of polycarbonate for children. Eichhorst points out that the AOA does not have the capability of doing a more definitive search on this subject since such a requirement might be found in a state regulation rather than a statute. At this point, the answer is that a computer search of state statutes could find no requirement of poly only for children. If an Eyecare Business reader knows of such a requirement, we would appreciate hearing about it. EB

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